| Symptoms |
Potential problems |
Remedy |
|
|
|
|
Display not working, wrong digit displayed
|
Cracked solder joints |
Resolder display |
| All LED's are on when powering on unit |
Reset Generator defective |
Replace U 24 |
| Nothing comes on at power up |
check fuses, Reset generator |
Replace fuses, replace U24 reset gen. |
| U22 gets hot |
Latches defective |
Replace U4, U8 |
|
Cracked solder joints on display |
|
| No receive, no techmode control |
Ribbon cable between radio and interface board is twisted out of it's zero
insertion force connector
|
Remove the interface board and re-insert the cable straight into the connector |
| Cannot align audio levels properly |
An updated radio is used together with a non updated controller board
An updated radio can be recognized by an 18K resistor standing on edge
on the interface board and on an updated Rev 6 controller board R41 is 3.9K
|
Non updated controller boards where |
| Unit does not power up, on LED blinks |
Small red power wire is squeezed between radio chassis and main chassis |
Remove radio and re-route the red power lead to the other side
behind the 26 pin ribbon cable to prevent it from accidentially shorting
|
| Scrambler not working |
Rev 6 and earlier controller boards can have erratic scrambler operation if the MX631 SPM detector
U36 is not installed. On later boards a 100K resistor is placed between pins 1 and 2 of U32 to remedy
this problem.
|
Install U36 or place a 100K resistor between pins 1 and 2 of U32. |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|